[PATCH 2/2] mmc: fix mmc card disappearence on resume on ricoh mmc controllers

From: Maxim Levitsky
Date: Sun Jun 06 2010 - 17:29:14 EST


The reason was that it takes time for controller to detect the card.
So wait a bit for the card to appear.
In worst case scenario, when you suspend the system with mmc card,
and actually remove it, the resume will be delayed maximum by 2 seconds

Signed-off-by: Maxim Levitsky <maximlevitsky@xxxxxxxxx>
---
drivers/mmc/host/sdhci-pci.c | 3 ++-
drivers/mmc/host/sdhci.c | 18 ++++++++++++++++++
drivers/mmc/host/sdhci.h | 2 ++
3 files changed, 22 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index c4bcaeb..49d863c 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -115,7 +115,8 @@ static const struct sdhci_pci_fixes sdhci_ricoh_mmc = {
.quirks = SDHCI_QUIRK_32BIT_DMA_ADDR |
SDHCI_QUIRK_CLOCK_BEFORE_RESET |
SDHCI_QUIRK_NO_CARD_NO_RESET |
- SDHCI_QUIRK_MISSING_CAPS
+ SDHCI_QUIRK_MISSING_CAPS |
+ SDHCI_QUIRK_WAIT_CARD_ON_RESUME
};

static const struct sdhci_pci_fixes sdhci_ene_712 = {
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 483b78e..6cda505 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1612,6 +1612,24 @@ int sdhci_resume_host(struct sdhci_host *host)
{
int ret;

+ /* Some controllers (especialy the ricoh mmc controller) delay
+ card detection on resume (probably since the controller
+ has to poke the card to determine if its MMC or not */
+
+ if (host->mmc->bus_ops && (host->quirks &
+ SDHCI_QUIRK_WAIT_CARD_ON_RESUME)) {
+
+ unsigned long timeout = jiffies + msecs_to_jiffies(2000);
+
+ while (!time_after(jiffies, timeout))
+ if (sdhci_readl(host, SDHCI_PRESENT_STATE)
+ & SDHCI_CARD_PRESENT) {
+ break;
+ }
+ cpu_relax();
+ }
+
+
if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
if (host->ops->enable_dma)
host->ops->enable_dma(host);
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index b1839a3..c9d099c 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -242,6 +242,8 @@ struct sdhci_host {
#define SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC (1<<26)
/* Controller is missing device caps. Use caps provided by host */
#define SDHCI_QUIRK_MISSING_CAPS (1<<27)
+/* Card doesn't appear immediatly on resume from low power state */
+#define SDHCI_QUIRK_WAIT_CARD_ON_RESUME (1<<28)

int irq; /* Device IRQ */
void __iomem * ioaddr; /* Mapped address */
--
1.7.0.4

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